<template>
    <div class="cmt-container">
        <h3>发表评论</h3>
        <hr>
        <textarea placeholder="请输入要评论的内容(最多120字)" maxlength="120" v-model="msg"></textarea>
        <mt-button type="primary" size="large" @click="postComment">发表评论</mt-button>
        <div class="cmt-list">
            <div class="cmt-item" v-for="(item,i) in comments" :key="i">
                <div class="cmt-title">
                    第{{i+1}}楼&nbsp;&nbsp;用户：{{item.user_name}}&nbsp;&nbsp;发表时间：{{item.add_time | dateFormat}}
                </div>
                <div class="cmt-body">
                    {{item.content === 'undefined' ? '此用户很懒，什么都没干':item.content}}
                </div>
            </div>
        </div>
        <mt-button type="danger" size="large" plain @click="getMore">加载更多</mt-button>
    </div>
</template>

<script>
import {Toast} from 'mint-ui'
export default{
    data(){
        return {
            pageIndex: 1, //默认显示第一页数据
            comments: [],
            msg: ''
        }
    },
    created(){
        this.getComments()
    },
    methods: {
        getComments(){
            this.$http.get('api/getcomments/'+this.id+"?pageindex="+
            this.pageIndex).then(result=>{
                if(result.body.status === 0){
                    // this.comments = result.body.message
                    //每当获取新评论数据的时候，不要把老数据清空覆盖，而是以老数据拼接上新数据
                    this.comments = this.comments.concat(result.body.message)
                }else{
                   alert('获取数据失败')
                }
            })
        },
        getMore(){
            this.pageIndex++;
            this.getComments();
        },
        postComment(){
            //校验是否为空内容,trim()去掉空格
            if(this.msg.trim().length === 0){
               return Toast('评论内容不能为空');
            }
            //参数1、请求的url地址
            //参数2、提交给服务器的数据对象 {content:this.msg}
            //参数3、定义提交时候，表单中数据的格式(emulateJSON:json)
            this.$http
            .post('api/postcomment/'+this.$route.params.id,{
                content:this.msg.trim()
            })
            .then(function(result){
                if(result.body.status === 0){
                    //拼接出一个评论对象
                    var cmt = {
                        user_name: '匿名用户',
                        add_time:Date.now(),
                        content: this.msg.trim()
                        }
                    this.comments.unshift(cmt)
                    this.msg = ""
                }
            })
        }
    },
    props: ["id"]
}
</script>

<style>
.cmt-container h3{
    font-size: 18px;
}
textarea {
    font-size: 14px;
    height: 85px;
    margin: 0;
}
.cmt-list{
    margin: 5px 0;
}
.cmt-list .cmt-item {
    font-size: 13px
}
.cmt-list .cmt-item .cmt-title {
    background-color: #ccc;
    line-height: 30px;
}
.cmt-list .cmt-item .cmt-body {
    line-height: 35px;
    text-indent: 2em;
}
</style>

